Male Hypogonadism

[madman]

 

[madman]

 

[madman]

 

[madman]

 

[madman]

 

[madman]

 

[madman]

@Nelson Vergel

 

[madman]

 

[madman]

 

[madman]

 

[madman]

 

[madman]

 

[madman]

 

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[Cataceous]

I think these statements by Richard Quinton are worth reiterating. Personal experience had already left me with reduced confidence in some mass spectrometry testing. Perhaps harmonized testing will overcome these problems.

1. Although tandem mass spectrometry (MS) for T level in the female range is superior to immunoassays, some immunoassays outperform MS methods in the male range.​

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2. Between-laboratory agreement for some immunoassays can be as good as 4% CV, whereas MS users vary by up to +10%.​

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3. Therefore, MS is by no means the gold standard that was previously supposed.​

 

[tareload]

About as good as you are going to get best case with routine and methodical calibration.

Comparison of four clinically validated testosterone LC-MS/MS assays: Harmonization is an attainable goal

Immunoassays and liquid chromatography-tandem mass spectrometry assays are commonly employed in clinical laboratories for measurement of total testosterone in serum. Results obtained from either of these methodologies compare poorly due to differences ...

www.ncbi.nlm.nih.gov

Methods​

This study compares the results from four independently developed and validated LC-MS/MS assays for total testosterone. The calibration for each assay was verified using National Institute of Standards and Technology Standard Reference Material 971.

Conclusions​

Excellent agreement between four independently developed LC-MS/MS assays demonstrates that harmonization using standard reference material is attainable. However, as we found in this study, to ensure accurate calibration it is critical to validate the concentrations of new lots of calibrators

 

[tareload]

https://www.cdc.gov/labstandards/pdf/hs/CDC_Certified_Testosterone_Assays-508.pdf

HoSt/VDSCP Certified Participants | CDC

CDC offers quality assurance (QA) and standardization programs to help laboratories improve the quality and reliability of their measurement procedures.

www.cdc.gov

Testosterone in Serum​

The following laboratories have successfully passed the performance criterion ±6.4% mean bias to the CDC Testosterone Reference Method over the concentration range of 2.50-1,000 ng/dL. Laboratories are awarded certificates for successfully completing bias testing using specific methods, reagent lots, calibrator lots and instrumentation. During the year it is the responsibility of the participant to ensure that the results of their method remain consistent over time, throughout the year, between lots, and over the measurement range reported. It is not the intent of the CDC HoSt Program to certify each lot of reagents, or to issue certification beyond the measurement range of 2.50-1,000 ng/dL, at this time.

 

[madman]

TRT and the Prostate

Testosterone Treatment and the Risk of Prostate Adverse Events (2022) Jason A. Levy, DO, MS, Arthur L. Burnett, MD, MBA, Adrian S. Dobs, MD, MHS INTRODUCTION Definition Hypogonadism is a clinical syndrome that results from failure of the testis to produce physiologic concentrations of...

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TRT and Cardiovascular Disease

Testosterone replacement therapy and cardiovascular disease (2022) Jeremy M. Auerbach and Mohit Khera The use of testosterone therapy has a complex history of apprehension and questions regarding its safety. Despite an eventual consensus that testosterone therapy was safe and effective...

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